Question

3x-4y = 10 and xy= -2, Find the value of 9x² + 16 y²​

Answer 1

Answer:

$(x + y) {}^{2} = x {}^{2} + 2xy + y {}^{2}$

Step-by-step explanation:

USING THE ABOVE FORMULA:

$(3x - 4y) {}^{2} = 9x {}^{2} - 24xy + 16y {}^{2} \\ 10 {}^{2} = 9x {}^{2} - 24( - 2) + 16y {}^{2} \\ 100 = 9x {}^{2} + 48 + 16y {}^{2} \\ 9x {}^{2} + 16y {}^{2} = 100 - 48 \\ = 52$